Metabolism, basal

Basal metabolic rate The rate of oxygen consumption by a person at rest. 

Grund-sebicht, /. primary layer, fundamental layer ground course, -stein, m. foundation stone, cornerstone lower (mill) stone, -stock, m. matrix, -stoff, m. element raw material base Paper) ground pulp, -stofflndustrie, /. basic industry, -stoff-wechsel, m. basal metabolism, -stricb, m. first coat, priming down stroke, -stuck, m. premises, (real) property. -substanz, /. element basic substance Anat.) ground substance, matrix, -teil, m. element, principle basic part, -teilcben, n. fundamental particle, -ton, m. fundamental tone, primary tone, -umsatz, m. Biol.) basal metabolism. 

The basal metabolic rate for adults is 1 to 1.2 Calories/minute or 60 to 72 Calories/hour. This energy powers the movement of the chest during respiration and the beating of the heart—processes that are obviously necessary for life. However, a surprisingly large fraction of the BMR is used by cells to maintain ionic gradients between their interior and the fluid that surrnunds them (the interstitial fluid nr tissue fluid). 

Animal nutritionists have developed formulas to guide them in recommending the amount of food to feed animals in captive situations such as in zoos. First, the number of calorics needed to maintain the animal while at rest is determined—this is called the basal metabolic rate (BMR). In general, a reptile s BMR is only 15 percent that of a placental mammal, while a bird s is quite a bit higher than both a reptile s and a mammal s. For all animals, the number of calories they should receive on a maintenance diet is twice that used at the basal metabolic rate. A growing animal should receive three times the number of calories at the BMR, while an animal in the reproductive phase should receive four to six times the BMR. 

The average basal metabolic rate for humans is about 65 keal/h, or 1600 keal/day. Obviously, the rate varies for different people depending ori sex, age, weight, and physical condition. As a rule, the BMR is Jow er for older people than for younger people, is lower for females than for males, and is lower for people in good physical condition than for those who are out of shape and overweight. A BMR substantially above the expected value indicates an unusually rapid metabolism, perhaps caused by a fever or some biochemical abnormality. 

Backbone (protein), 1028 Backside displacement. reaction and.363-364 von Baeyer, Adolf, 113 Baeyer strain theory, 113-114 Bakelile, structure of, 1218 Banana, esters in, 808 Barton, Derek, H. R., 389 Basal metabolic rate, 1169 Basal metabolism. 1169-1170 Base, Bronsted-Lowry, 49 Lewis, 57, 59-60 organic, 56-57 strengths of, 50-52 Base pair (DNA), 1103-1105 electrostatic potential maps of. 

Some Conclusions about Biological Chemistry 1169 Focus On... Basal Metabolism 1169... 

Triiodothyronine (3, 5,3-L-triiodothyronine, T3) is a thyroid hormone. It is producedby outer ring deiodination of thyroxine (T4) in peripheral tissues. The biologic activity of T3 is 3-8 times higher than that of T4. T3 is 99.7% protein-bound and is effective in its free non-protein-bound form. The half-life of triiodothyronine is about 19 h. The daily tur nover of T3 is 75%. Triiodothyronine acts via nuclear receptor binding with subsequent induction of protein synthesis. Effects of thyroid hormones are apparent in almost all organ systems. They include effects on the basal metabolic rate and the metabolisms of proteins, lipids and carbohydrates. 

Most CF patients have an increased caloric need due to increased energy expenditure through increased work of breathing and increased basal metabolism. Prevention of malnutrition requires early nutritional intervention. In patients with mild lung disease and well-controlled absorption, required caloric intake is approximately 100% to 120% of the recommended daily allowance (RDA) for age.15 As lung disease progresses, caloric requirements increase. 

Sipilainen R, Uusitupa M, Heikkinen S, Rissanen A, Laakso M. Polymorphism of the / 3-adrenergic receptor gene affects basal metabolic rate in obese Finns. Diabetes 1997 46 77-80. 

Daily energy requirements for children are approximately 150% of basal metabolic rate with additional calories to support activity and growth (Table 57-5). Requirements increase with fever, sepsis, major surgery, trauma, burns, long-term growth failure, and chronic conditions (e.g., bronchopulmonary dysplasia, congenital heart disease, and cystic fibrosis). 

There is a decrease in basal metabolic rate with a decline in lean body mass and less physical activity. The caloric requirement may, therefore, be reduced... 

Body composition varies with age. The pediatric population has unique physiologic needs that make nutritional requirements distinctly different than adults. In children, caloric requirements per kilogram are higher because of their higher basal metabolic rate (BMR). BMR is approximately 50-55 kcal/ kg/day in infancy and declines to about 20-25 kcal/kg/day during adolescence. 

By definition all hormones affect the behavior of their target cells. Examples of the interplay between endocrine disturbances and their biochemical consequences are provided by some of the diseases of the thyroid, which directly affects basal metabolic rate, and diabetes mellitus, where glucose metabolism is deranged. 

The power required to sustain physiological processes can be calculated by using the above equation. If a pressure-volume loop for a respiratory cycle is plotted, the work of breathing may be found. If the respiratory rate is now measured then the power may be calculated. The power required for respiration is only approximately 700-1000 mW, compared with approximately 80 W needed at basal metabolic rate. 

Food intake is one side of the body weight equation energy expenditure is the other. One aspect of energy expenditure is our basal metabolic rate. That is the rate of which we consume energy when at rest. Basal metabolic rates vary significantly from person... 

---